package com.itheima.fliter;


import com.alibaba.fastjson.JSON;
import com.itheima.common.BaseContext;
import com.itheima.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Slf4j
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest)servletRequest;
        HttpServletResponse response = (HttpServletResponse)servletResponse;
//        filterChain.doFilter(request,response);

        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求{}",requestURI);

        //定义不需要处理的请求路径
        String[] urls= new String[]{
          "/employee/login",
          "/employee/logout",
          "/backend/**",
          "/front/**",
          "/common/**",
          "/user/sendMsg",
          "/user/login"
        };

        //2.判断本次请求是否需要处理
        boolean check = check(urls, requestURI);

        //3.如果不需要处理，则直接放行
        if (check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1.判断登录状态，如果已登录，则直接放行
        if (null != request.getSession().getAttribute("employee")){
            log.info("用户已登录，用户id为:{}",request.getSession().getAttribute("employee"));

            long cid = Thread.currentThread().getId();
            log.info("当前线程：{}",cid);

            Long id = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(id);

            filterChain.doFilter(request,response);
            return;
        }
        //4-2.判断登录状态，如果已登录，则直接放行
        if (null != request.getSession().getAttribute("user")){
            log.info("用户已登录，用户id为:{}",request.getSession().getAttribute("user"));

            Long userid = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userid);

            filterChain.doFilter(request,response);
            return;
        }

        //5.如果未登录，则返回未登录的结果（通过输出流方式向客户端响应页面请求结果）
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /*
    * 路径匹配检查本次匹配是否需要放行
    * */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url,requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
